This invention is directed to multifunctional lubricant additives particularly useful as friction modifiers and oxidation inhibitors and high temperature stabilizing additives for hydrocarbyl lubricants and fuels; to compositions containing same and to means for increasing the fuel consumption of internal combustion or turbine engines. More particularly, this invention is directed to partially borated, partial carboxylic acid reaction products of N-hydrocarbylhydrocarbylene diamines and to lubricant fluids containing said partially borated compounds.
Metal surfaces of machinery or engines operating under heavy loads wherein metal slides against metal can undergo excessive wear or corrosion. Lubricants used to protect against this are prone to oxidative deterioration when subjected to elevated temperatures or when exposed to atmospheric conditions for long periods of time. Accordingly, there is a continuing need for effective multifunctional additive systems capable of effectively reducing wear, modifying frictional characteristics and reducing oxidative deterioration.
U.S. Pat. No. 3,652,410 describes multifunctional lubricant additive compositions comprising over-based metal salts and sulfur containing compounds.
U.S. Pat. No. 4,162,224 describes antiwear and antioxidant additives comprising certain borates of bis-oxazolines.
U.S. Pat. No. 4,368,129 describes multifunctional lubricant additives and compositions thereof comprising metal salts of partially borated, partially phosphosulfurized polyols and hydroxyl containing esters which are effective friction reducing and antioxidant additives when used in various lubricating media.
Amines, amine adducts, amides, and amino-amides have also found wide spread use as lubricating oil, grease and fuel additives. However, it has now been discovered that borates of alkyl diamine-carboxylic acid reaction products possess significant and highly effective friction reducing and high temperature stabilizing properties. To the best of applicant's knowledge and belief, neither the subject partially borated alkyl diamine carboxylic acid reaction products nor lubricating compositions or fuel compositions containing same were known heretofore.